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Study Of A Nanoscale Water Cluster By Atomic Force Microscopy, Manhee Lee, Baekman Sung, Nicole N. Hashemi, Wonho Jhe Jan 2009

Study Of A Nanoscale Water Cluster By Atomic Force Microscopy, Manhee Lee, Baekman Sung, Nicole N. Hashemi, Wonho Jhe

Nastaran Hashemi

We present a novel method for investigating a nanometric cluster of water molecules, which includes the formation and manipulation of nanometric water, and the measurement of its mechanical properties. The atomic force microscope based on the quartz tuning-fork sensor is employed to form and manipulate the nanometric water, and the theoretical tool of amplitude-modulation atomic force microscopy is used to obtain the elasticity, viscosity and dissipation energy of it. With high vertical resolution less than [similar]0.1 nm and high force sensitivity of [similar]0.01 N m−1, this tool facilitates the stable formation and manipulation of a nano-water cluster ([similar]104 molecules) in …


The Development And Implementation Of A Nanotechnology Module Into A Large, Freshman Engineering Course, Vinod Lohani, Ganesh Balasubramanian, Ishwar Puri, Scott Case, Roop Mahajan Jan 2009

The Development And Implementation Of A Nanotechnology Module Into A Large, Freshman Engineering Course, Vinod Lohani, Ganesh Balasubramanian, Ishwar Puri, Scott Case, Roop Mahajan

Ganesh Balasubramanian

The development and implementation of a nanotechnology learning module into a freshman engineering course in Virginia Tech’s large engineering program is discussed. This module, a part of a spiral theory based nanotechnology option that will be implemented in the curriculum of the Engineering Science Mechanics (ESM) department at Virginia Tech, was piloted with ~180 freshmen in Spring ’08. The pilot included a prior knowledge survey, a 40-minute in-class presentation on nanotechnology, a hands-on module involving analysis of nanoscale images, plotting of force functions at atomic scale using LABVIEW, and a post-module survey. Students’ misconceptions, observed through the prior knowledge survey, …


Rhodium Nanoparticle Shape Dependence In The Reduction Of No By Co, James Russell Renzas, Yawen Zhang, Wenyu Huang, Gabor Somoraji Jan 2009

Rhodium Nanoparticle Shape Dependence In The Reduction Of No By Co, James Russell Renzas, Yawen Zhang, Wenyu Huang, Gabor Somoraji

Wenyu Huang

The shape dependence of the catalytic reduction of nitric oxide by carbon monoxide on rhodium nanopoly- hedra and nanocubes was studied from 230 to 270 ° C. The nanocubes are found to exhibit higher turnover frequency and lower activation energy than the nanopolyhedra. These trends are compared to previous studies on Rh single crystals.


Sub-10 Nm Platinum Nanocrystals With Size And Shape Control: Catalytic Study For Ethylene And Pyrrole Hydrogenation, Chia-Kuang Tsung, John N. Kuhn, Wenyu Huang, Cesar Aliaga, Ling-I Hung, Gabor A. Somorjai, Peidong Yang Jan 2009

Sub-10 Nm Platinum Nanocrystals With Size And Shape Control: Catalytic Study For Ethylene And Pyrrole Hydrogenation, Chia-Kuang Tsung, John N. Kuhn, Wenyu Huang, Cesar Aliaga, Ling-I Hung, Gabor A. Somorjai, Peidong Yang

Wenyu Huang

Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported …


Self-Organized Ultrathin Oxide Nanocrystals, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Melissa Fardy, Ruoxue Yan, Xiaofeng Zhang, Yandong Li, Peidong Yang Jan 2009

Self-Organized Ultrathin Oxide Nanocrystals, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Melissa Fardy, Ruoxue Yan, Xiaofeng Zhang, Yandong Li, Peidong Yang

Wenyu Huang

Sub-2-nm (down to one-unit cell) uniform oxide nanocrystals and highly ordered superstructures were obtained in one step using oleylamine and oleic acid as capping and structure directing agents. The cooperative nature of the nanocrystal growth and assembly resulted in mesoscopic one-dimensional ribbon-like superstructures made of these ultrathin nanocrystals. The process reported here is general and can be readily extended to the production of many other transition metal (TiO2, ZnO, Nb2O5) and rare earth oxide (Eu2O3, Sm2O3, Er2O3, Y2O3, Tb2O3, and Yb2O3) systems.